From 550b1798a169d07139f8f079bc5c83271a181f7f Mon Sep 17 00:00:00 2001
From: Eugene Burkov <e.burkov@adguard.com>
Date: Wed, 18 Aug 2021 13:20:56 +0300
Subject: [PATCH] Pull request: 3457 fix service reload
Merge in DNS/adguard-home from 3457-darwin-svc-reload to master
Closes #3457.
Squashed commit of the following:
commit e3d6fbccf8373194360b6480e2d702ccd0ec7107
Author: Eugene Burkov <e.burkov@adguard.com>
Date: Wed Aug 18 00:52:39 2021 +0300
aghos: imp docs
commit 220d37ebc1e0c2e9ba37a34650bff1480bd2fcf6
Author: Eugene Burkov <e.burkov@adguard.com>
Date: Tue Aug 17 15:45:52 2021 +0300
all: fix ps
---
CHANGELOG.md | 2 +
internal/aghnet/systemresolvers_windows.go | 10 +--
internal/aghos/os.go | 98 ++++++++++++++++++++--
internal/aghos/os_bsd.go | 4 -
internal/aghos/os_freebsd.go | 4 -
internal/aghos/os_linux.go | 4 -
internal/aghos/os_test.go | 98 ++++++++++++++++++++++
internal/aghos/os_windows.go | 6 --
internal/home/service.go | 47 ++++++-----
9 files changed, 220 insertions(+), 53 deletions(-)
create mode 100644 internal/aghos/os_test.go
diff --git a/CHANGELOG.md b/CHANGELOG.md
index 08b14548..8c1138c8 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -65,6 +65,7 @@ and this project adheres to
### Fixed
+- `reload` service action on macOS and FreeBSD ([#3457]).
- Inaccurate using of service actions in the installation script ([#3450]).
- Client ID checking ([#3437]).
- Discovering other DHCP servers on `darwin` and `freebsd` ([#3417]).
@@ -128,6 +129,7 @@ and this project adheres to
[#3435]: https://github.com/AdguardTeam/AdGuardHome/issues/3435
[#3437]: https://github.com/AdguardTeam/AdGuardHome/issues/3437
[#3450]: https://github.com/AdguardTeam/AdGuardHome/issues/3450
+[#3457]: https://github.com/AdguardTeam/AdGuardHome/issues/3457
diff --git a/internal/aghnet/systemresolvers_windows.go b/internal/aghnet/systemresolvers_windows.go
index 584b3636..6341ef4f 100644
--- a/internal/aghnet/systemresolvers_windows.go
+++ b/internal/aghnet/systemresolvers_windows.go
@@ -13,8 +13,6 @@ import (
"sync"
"time"
- "github.com/AdguardTeam/AdGuardHome/internal/aghio"
- "github.com/AdguardTeam/AdGuardHome/internal/aghos"
"github.com/AdguardTeam/golibs/errors"
"github.com/AdguardTeam/golibs/log"
)
@@ -115,12 +113,6 @@ func (sr *systemResolvers) getAddrs() (addrs []string, err error) {
return nil, fmt.Errorf("getting the command's stdout pipe: %w", err)
}
- var stdoutLimited io.Reader
- stdoutLimited, err = aghio.LimitReader(stdout, aghos.MaxCmdOutputSize)
- if err != nil {
- return nil, fmt.Errorf("limiting stdout reader: %w", err)
- }
-
go writeExit(stdin)
err = cmd.Start()
@@ -128,7 +120,7 @@ func (sr *systemResolvers) getAddrs() (addrs []string, err error) {
return nil, fmt.Errorf("start command executing: %w", err)
}
- s := bufio.NewScanner(stdoutLimited)
+ s := bufio.NewScanner(stdout)
addrs = scanAddrs(s)
err = cmd.Wait()
diff --git a/internal/aghos/os.go b/internal/aghos/os.go
index 2ecd87b2..7eb0b3cf 100644
--- a/internal/aghos/os.go
+++ b/internal/aghos/os.go
@@ -4,10 +4,16 @@
package aghos
import (
+ "bufio"
"fmt"
+ "io"
"os/exec"
+ "path"
"runtime"
- "syscall"
+ "strconv"
+ "strings"
+
+ "github.com/AdguardTeam/golibs/log"
)
// UnsupportedError is returned by functions and methods when a particular
@@ -43,11 +49,6 @@ func HaveAdminRights() (bool, error) {
return haveAdminRights()
}
-// SendProcessSignal sends signal to a process.
-func SendProcessSignal(pid int, sig syscall.Signal) error {
- return sendProcessSignal(pid, sig)
-}
-
// MaxCmdOutputSize is the maximum length of performed shell command output.
const MaxCmdOutputSize = 2 * 1024
@@ -65,6 +66,91 @@ func RunCommand(command string, arguments ...string) (int, string, error) {
return cmd.ProcessState.ExitCode(), string(out), nil
}
+// PIDByCommand searches for process named command and returns its PID ignoring
+// the PIDs from except. If no processes found, the error returned.
+func PIDByCommand(command string, except ...int) (pid int, err error) {
+ // Don't use -C flag here since it's a feature of linux's ps
+ // implementation. Use POSIX-compatible flags instead.
+ //
+ // See https://github.com/AdguardTeam/AdGuardHome/issues/3457.
+ cmd := exec.Command("ps", "-A", "-o", "pid=", "-o", "comm=")
+
+ var stdout io.ReadCloser
+ if stdout, err = cmd.StdoutPipe(); err != nil {
+ return 0, fmt.Errorf("getting the command's stdout pipe: %w", err)
+ }
+
+ if err = cmd.Start(); err != nil {
+ return 0, fmt.Errorf("start command executing: %w", err)
+ }
+
+ var instNum int
+ pid, instNum, err = parsePSOutput(stdout, command, except...)
+ if err != nil {
+ return 0, err
+ }
+
+ if err = cmd.Wait(); err != nil {
+ return 0, fmt.Errorf("executing the command: %w", err)
+ }
+
+ switch instNum {
+ case 0:
+ // TODO(e.burkov): Use constant error.
+ return 0, fmt.Errorf("no %s instances found", command)
+ case 1:
+ // Go on.
+ default:
+ log.Info("warning: %d %s instances found", instNum, command)
+ }
+
+ if code := cmd.ProcessState.ExitCode(); code != 0 {
+ return 0, fmt.Errorf("ps finished with code %d", code)
+ }
+
+ return pid, nil
+}
+
+// parsePSOutput scans the output of ps searching the largest PID of the process
+// associated with cmdName ignoring PIDs from ignore. Valid r's line shoud be
+// like:
+//
+// 123 ./example-cmd
+// 1230 some/base/path/example-cmd
+// 3210 example-cmd
+//
+func parsePSOutput(r io.Reader, cmdName string, ignore ...int) (largest, instNum int, err error) {
+ s := bufio.NewScanner(r)
+ScanLoop:
+ for s.Scan() {
+ fields := strings.Fields(s.Text())
+ if len(fields) != 2 || path.Base(fields[1]) != cmdName {
+ continue
+ }
+
+ cur, aerr := strconv.Atoi(fields[0])
+ if aerr != nil || cur < 0 {
+ continue
+ }
+
+ for _, pid := range ignore {
+ if cur == pid {
+ continue ScanLoop
+ }
+ }
+
+ instNum++
+ if cur > largest {
+ largest = cur
+ }
+ }
+ if err = s.Err(); err != nil {
+ return 0, 0, fmt.Errorf("scanning stdout: %w", err)
+ }
+
+ return largest, instNum, nil
+}
+
// IsOpenWrt returns true if host OS is OpenWrt.
func IsOpenWrt() (ok bool) {
return isOpenWrt()
diff --git a/internal/aghos/os_bsd.go b/internal/aghos/os_bsd.go
index d8557b43..48b76609 100644
--- a/internal/aghos/os_bsd.go
+++ b/internal/aghos/os_bsd.go
@@ -20,10 +20,6 @@ func haveAdminRights() (bool, error) {
return os.Getuid() == 0, nil
}
-func sendProcessSignal(pid int, sig syscall.Signal) error {
- return syscall.Kill(pid, sig)
-}
-
func isOpenWrt() (ok bool) {
return false
}
diff --git a/internal/aghos/os_freebsd.go b/internal/aghos/os_freebsd.go
index b3ec7e77..33cd9d3f 100644
--- a/internal/aghos/os_freebsd.go
+++ b/internal/aghos/os_freebsd.go
@@ -20,10 +20,6 @@ func haveAdminRights() (bool, error) {
return os.Getuid() == 0, nil
}
-func sendProcessSignal(pid int, sig syscall.Signal) error {
- return syscall.Kill(pid, sig)
-}
-
func isOpenWrt() (ok bool) {
return false
}
diff --git a/internal/aghos/os_linux.go b/internal/aghos/os_linux.go
index 5b1e5e87..349fc18a 100644
--- a/internal/aghos/os_linux.go
+++ b/internal/aghos/os_linux.go
@@ -25,10 +25,6 @@ func haveAdminRights() (bool, error) {
return os.Getuid() == 0, nil
}
-func sendProcessSignal(pid int, sig syscall.Signal) error {
- return syscall.Kill(pid, sig)
-}
-
func isOpenWrt() (ok bool) {
var err error
ok, err = FileWalker(func(r io.Reader) (_ []string, cont bool, err error) {
diff --git a/internal/aghos/os_test.go b/internal/aghos/os_test.go
new file mode 100644
index 00000000..0ca567d8
--- /dev/null
+++ b/internal/aghos/os_test.go
@@ -0,0 +1,98 @@
+package aghos
+
+import (
+ "bytes"
+ "testing"
+
+ "github.com/AdguardTeam/AdGuardHome/internal/aghio"
+ "github.com/stretchr/testify/assert"
+ "github.com/stretchr/testify/require"
+)
+
+func TestLargestLabeled(t *testing.T) {
+ const (
+ comm = `command-name`
+ nl = "\n"
+ )
+
+ testCases := []struct {
+ name string
+ data []byte
+ wantPID int
+ wantInstNum int
+ }{{
+ name: "success",
+ data: []byte(nl +
+ ` 123 not-a-` + comm + nl +
+ ` 321 ` + comm + nl,
+ ),
+ wantPID: 321,
+ wantInstNum: 1,
+ }, {
+ name: "several",
+ data: []byte(nl +
+ `1 ` + comm + nl +
+ `5 /` + comm + nl +
+ `2 /some/path/` + comm + nl +
+ `4 ./` + comm + nl +
+ `3 ` + comm + nl +
+ `10 .` + comm + nl,
+ ),
+ wantPID: 5,
+ wantInstNum: 5,
+ }, {
+ name: "no_any",
+ data: []byte(nl +
+ `1 ` + `not-a-` + comm + nl +
+ `2 ` + `not-a-` + comm + nl +
+ `3 ` + `not-a-` + comm + nl,
+ ),
+ wantPID: 0,
+ wantInstNum: 0,
+ }, {
+ name: "weird_input",
+ data: []byte(nl +
+ `abc ` + comm + nl +
+ `-1 ` + comm + nl,
+ ),
+ wantPID: 0,
+ wantInstNum: 0,
+ }}
+
+ for _, tc := range testCases {
+ r := bytes.NewReader(tc.data)
+
+ t.Run(tc.name, func(t *testing.T) {
+ pid, instNum, err := parsePSOutput(r, comm)
+ require.NoError(t, err)
+
+ assert.Equal(t, tc.wantPID, pid)
+ assert.Equal(t, tc.wantInstNum, instNum)
+ })
+ }
+
+ t.Run("scanner_fail", func(t *testing.T) {
+ lr, err := aghio.LimitReader(bytes.NewReader([]byte{1, 2, 3}), 0)
+ require.NoError(t, err)
+
+ target := &aghio.LimitReachedError{}
+ _, _, err = parsePSOutput(lr, "")
+ require.ErrorAs(t, err, &target)
+
+ assert.EqualValues(t, 0, target.Limit)
+ })
+
+ t.Run("ignore", func(t *testing.T) {
+ r := bytes.NewReader([]byte(nl +
+ `1 ` + comm + nl +
+ `2 ` + comm + nl +
+ `3` + comm + nl,
+ ))
+
+ pid, instances, err := parsePSOutput(r, comm, 1, 3)
+ require.NoError(t, err)
+
+ assert.Equal(t, 2, pid)
+ assert.Equal(t, 1, instances)
+ })
+}
diff --git a/internal/aghos/os_windows.go b/internal/aghos/os_windows.go
index 8972e7b5..bff5a3f0 100644
--- a/internal/aghos/os_windows.go
+++ b/internal/aghos/os_windows.go
@@ -4,8 +4,6 @@
package aghos
import (
- "syscall"
-
"golang.org/x/sys/windows"
)
@@ -34,10 +32,6 @@ func haveAdminRights() (bool, error) {
return true, nil
}
-func sendProcessSignal(pid int, sig syscall.Signal) error {
- return Unsupported("kill")
-}
-
func isOpenWrt() (ok bool) {
return false
}
diff --git a/internal/home/service.go b/internal/home/service.go
index c1b88af9..3b2216d0 100644
--- a/internal/home/service.go
+++ b/internal/home/service.go
@@ -97,41 +97,48 @@ func sendSigReload() {
}
pidfile := fmt.Sprintf("/var/run/%s.pid", serviceName)
+ var pid int
data, err := os.ReadFile(pidfile)
if errors.Is(err, os.ErrNotExist) {
- var code int
- var psdata string
- code, psdata, err = aghos.RunCommand("ps", "-C", serviceName, "-o", "pid=")
- if err != nil || code != 0 {
- log.Error("finding AdGuardHome process: code: %d, error: %s", code, err)
+ if pid, err = aghos.PIDByCommand(serviceName, os.Getpid()); err != nil {
+ log.Error("finding AdGuardHome process: %s", err)
return
}
-
- data = []byte(psdata)
} else if err != nil {
log.Error("reading pid file %s: %s", pidfile, err)
return
+
+ } else {
+ parts := strings.SplitN(string(data), "\n", 2)
+ if len(parts) == 0 {
+ log.Error("can't read pid file %s: bad value", pidfile)
+
+ return
+ }
+
+ if pid, err = strconv.Atoi(strings.TrimSpace(parts[0])); err != nil {
+ log.Error("can't read pid file %s: %s", pidfile, err)
+
+ return
+ }
}
- parts := strings.SplitN(string(data), "\n", 2)
- if len(parts) == 0 {
- log.Error("Can't read PID file %s: bad value", pidfile)
+ var proc *os.Process
+ if proc, err = os.FindProcess(pid); err != nil {
+ log.Error("can't send signal to pid %d: %s", pid, err)
+
return
}
- pid, err := strconv.Atoi(strings.TrimSpace(parts[0]))
- if err != nil {
- log.Error("Can't read PID file %s: %s", pidfile, err)
+ if err = proc.Signal(syscall.SIGHUP); err != nil {
+ log.Error("Can't send signal to pid %d: %s", pid, err)
+
return
}
- err = aghos.SendProcessSignal(pid, syscall.SIGHUP)
- if err != nil {
- log.Error("Can't send signal to PID %d: %s", pid, err)
- return
- }
- log.Debug("Sent signal to PID %d", pid)
+
+ log.Debug("sent signal to PID %d", pid)
}
// handleServiceControlAction one of the possible control actions:
@@ -541,6 +548,6 @@ name="{{.Name}}"
{{.Name}}_user="root"
pidfile="/var/run/${name}.pid"
command="/usr/sbin/daemon"
-command_args="-P ${pidfile} -f -r {{.WorkingDirectory}}/{{.Name}}"
+command_args="-p ${pidfile} -f -r {{.WorkingDirectory}}/{{.Name}}"
run_rc_command "$1"
`